by Rachel George, USA TODAY Sport

by Rachel George, USA TODAY Sport

FORT LAUDERDALE â?? Johnny Manziel has mastered just about every defense he has faced, but dealing with being in the spotlight has been a learning process for the Texas A&M quarterback.

Responses to tweets he has posted and photos that have been taken of him since he won the Heisman Trophy last month have made the redshirt freshman phenom rethink his use of social media.

"It's tough knowing that everything you do is watched pretty closely because I'm doing the same stuff I've always done. It's just now people actually care what I do," he said Sunday as he and several other college football award winners met with the media at the Harbor Beach Marriott.

"It's hard to watch some of the stuff that people say to you when you take a picture or you do some stuff or you're at these games or whatever. It's tough to sit back, and you can't really defend yourself regardless of how much you want to scream out, 'I've been doing this forever. This is nothing new for me.'"

TMZ published photos on Sunday of Manziel, 20, celebrating the Aggies' Cotton Bowl win at Avenu Lounge in Dallas. In one of the photos, he appears to be holding a bottle of Dom Perignon. Since winning the Heisman he has had late-night appearances on the Jay Leno and David Letterman shows and been photographed courtside at a Dallas Mavericks game.

On Saturday, he posted a photo to Twitter of himself holding a handful of cash with the caption, "casino ballin."

He posted a follow-up tweet that said, "Nothing illegal about being 18+ in a casino and winning money...KEEP HATING!"

Manziel said he's still learning how to handle the notoriety, including what he should and shouldn't post on Twitter.

"I'm not doing anything wrong," he added. "Maybe there are times when I save myself a little grief and zip it up."

Manziel said Sunday he didn't know how much he won, but he came out ahead playing Roulette although he didn't win on his jersey No. 2.

"I'm still the same small town guy I've always been," he said. "For people to recognize me everywhere I go now and how much notoriety comes along with this, it's been beyond my wildest imagination."

Manziel became the first redshirt freshman to win the Heisman this year after leading ninth-ranked Texas A&M to a 10-2 regular season and a win at then-No. 1 Alabama. In the Aggies' Cotton Bowl win over Oklahoma on Friday, Manziel ran for an FBS-record 229 yards on 17 carries. He completed 22-of-34 passes for 287 yards, and he had four touchdowns (two rushing, two passing) in a 41-13 rout of No. 11 Oklahoma.

It was the first 11-win season for Texas A&M since 1998.

Speaking to media on Sunday, Manziel reflected on a whirlwind of travel since the College Football Awards on Dec. 7.

"I'm kind of eager to get back into school and let life slow down a little bit," he said.